With the current metagame, aggressive teams with high speed and high attack are all over the place. These never really suited my style, especially considering my favorite pokemon is the painfully slow Slowbro. That being the case, I formulated a team around the humble hermit crab and have been finding a great deal of success over the past week or so.
Team at a glance:
The team is built somewhat unconventionally, with many of my heavy hitters needing some setup to be effective. This tended to be a problem against hyper-offensive teams since my pokemon are all pretty slow on average, but the addition of Dusknoir catapulted the successes I found to a whole new level (I'll get into why later). Though I don't see the benefits of having a quick and powerful offense right off the bat, the defensive prowess coupled with the potential to be threatening after a turn or two can make countering this team very frustrating if you're not prepared.
Individually:
Venusaur @ Leftovers
252 HP / 156 Def / 100 SpD
Nature: Bold
Ability: Overgrow
-Sleep Powder
-Energy Ball
-Sludge Bomb
-Knock Off
The usage of Venusar actually came at the very end of the team's creation. I needed a bulky poison type able to soak up Toxic Spikes since they had such a destructive effect on half of my team. I initially considered Roserade for the job, but he didn't have the defensive strength I wanted to ensure that my poison type lived more than a few turns. This Venusaur operates in much the same way that the Roserade lead does, except with the incorporation of Knock Off to potentially cripple a second pokemon after putting one to sleep. I also chose Leftovers over Focus Sash since Venusaur has proven to have the bulk to survive an attack from many common leads anyway, nullifying any impact it could have. If I fear Venusaur may see an early demise, I'll typically opt to pull him out for one of my many tanks instead of risking his early exit.
Slowbro @ Leftovers
252 HP / 252 Def
Nature: Bold
Ability: Own Tempo
-Calm Mind
-Surf
-Ice Beam
-Slack Off
Calm Mind hits Slowbro exactly where he needs it: his special defense and special attack. Both are average on their own, but after a boost, they can reach rather threatening levels. Surf is the obligatory STAB, and Ice Beam is for coverage against dragons. Though this set is frustrated by other bulky waters, those lacking Toxic can't bring Slowbro down anyway, with the occasional exception of CroCune, so they provide little problem. Even though Swampert can hit against the unboosted Defense stat, his water neutrality makes it pretty easy to bring him down after a boost or two.
Breloom @ Toxic Orb
252 Atk / 252 Spe
Nature: Adamant
Ability: Poison Heal
-Spore
-Focus Punch
-Seed Bomb
-Substitute
What really needs to be said about this guy? He's incredibly annoying and can cripple one pokemon while slamming another on the switch. I initially had a problem having 2 pokemon with sleeping moves, but because they act so differently I've put up with it. Bulky fliers can give this set problems, but even they take a pretty significant hit on the switch from a beastly Focus Punch.
Umbreon @ Leftovers
252 HP / 104 Atk / 100 Def / 52 Def
Nature: Sassy
Ability: Synchronize
-Curse
-Wish
-Protect
-Payback
In addition to walling the dark or ghost attacks aimed at Slowbro, this Umbreon basically acts as the physical version of the CalmBro. Though having only one attack is unfortunate, having 100 base power (most of the time) with STAB and no immunities make this acceptable. Umbreon also has very deceptive bulk and can take hits from both sides incredibly well. Wish also gives Umbreon the ability to support the team should it be needed.
Dusknoir @ Leftovers
252 HP / 252 Def
Nature: Sassy
Ability: Pressure
-Trick Room
-Will-O-Wisp
-Pain Split
-Earthquake
Desperately needing something to take the bug attacks that plague many of my other pokemon, I turned to a bulky ghost. I initially used Rotom-H to fire back Overheats, but I've found that this Dusknoir has an incredible synergy with the overall terrible speed that my team has. Trick Room is a move that few people are prepared to counter, especially if they switch into Heatran expecting a Flash Fire boost. Earthquake is chosen as the lone attack for this exact case, since otherwise Dusknoir can do little to beat Heatran despite going first after a Trick Room. Will-O-Wisp helps tame Scizor that can cause a lot of problems, but also works on other physical threats to increase the odds of setting up Calm Minds or Curses. This was initially thought to act as a great support for the rest of my team, but Dusknoir's bulk and impressive attack can help him knock out a few foes on his own as well if the opponent is careless.
Scizor @ Choice Band
252 HP / 252 Atk
Nature: Adamant
Ability: Technician
-Bullet Punch
-U-Turn
-Superpower
-Pursuit
I always liked having a strong U-Turner to scout out opponents, and Scizor is simply the best at the job. His lone weakness is covered by my team's mascot, and the other beefy pokemon on my team can help sponge any other attacks that may be aimed in his direction. This Scizor also has the added bonus of Trick Room, should it be set up, since Scizor's speed is often his downfall.
Conclusion:
Slow and steady wins the race, as they say, and this team attempts to exemplify that. Though Slowbro and Umbreon have the overall bulk to take hits even after they've set up and are running through a team, their speed can often be a liability. Not so with the addition of Trick Room. Dusknoir also has the overall bulk to take a hit, set up Trick Room, then Pain Split damage away to keep itself healthy and running. Breloom is very annoying to anything slower than it, which can be everything depending on whether or not Trick Room is in play or not. The thing that makes this team shine, in my opinion, is that Trick Room simply acts as a bonus to make a set up easier instead of being necessary for success.
Team at a glance:






The team is built somewhat unconventionally, with many of my heavy hitters needing some setup to be effective. This tended to be a problem against hyper-offensive teams since my pokemon are all pretty slow on average, but the addition of Dusknoir catapulted the successes I found to a whole new level (I'll get into why later). Though I don't see the benefits of having a quick and powerful offense right off the bat, the defensive prowess coupled with the potential to be threatening after a turn or two can make countering this team very frustrating if you're not prepared.
Individually:

Venusaur @ Leftovers
252 HP / 156 Def / 100 SpD
Nature: Bold
Ability: Overgrow
-Sleep Powder
-Energy Ball
-Sludge Bomb
-Knock Off
The usage of Venusar actually came at the very end of the team's creation. I needed a bulky poison type able to soak up Toxic Spikes since they had such a destructive effect on half of my team. I initially considered Roserade for the job, but he didn't have the defensive strength I wanted to ensure that my poison type lived more than a few turns. This Venusaur operates in much the same way that the Roserade lead does, except with the incorporation of Knock Off to potentially cripple a second pokemon after putting one to sleep. I also chose Leftovers over Focus Sash since Venusaur has proven to have the bulk to survive an attack from many common leads anyway, nullifying any impact it could have. If I fear Venusaur may see an early demise, I'll typically opt to pull him out for one of my many tanks instead of risking his early exit.

Slowbro @ Leftovers
252 HP / 252 Def
Nature: Bold
Ability: Own Tempo
-Calm Mind
-Surf
-Ice Beam
-Slack Off
Calm Mind hits Slowbro exactly where he needs it: his special defense and special attack. Both are average on their own, but after a boost, they can reach rather threatening levels. Surf is the obligatory STAB, and Ice Beam is for coverage against dragons. Though this set is frustrated by other bulky waters, those lacking Toxic can't bring Slowbro down anyway, with the occasional exception of CroCune, so they provide little problem. Even though Swampert can hit against the unboosted Defense stat, his water neutrality makes it pretty easy to bring him down after a boost or two.

Breloom @ Toxic Orb
252 Atk / 252 Spe
Nature: Adamant
Ability: Poison Heal
-Spore
-Focus Punch
-Seed Bomb
-Substitute
What really needs to be said about this guy? He's incredibly annoying and can cripple one pokemon while slamming another on the switch. I initially had a problem having 2 pokemon with sleeping moves, but because they act so differently I've put up with it. Bulky fliers can give this set problems, but even they take a pretty significant hit on the switch from a beastly Focus Punch.

Umbreon @ Leftovers
252 HP / 104 Atk / 100 Def / 52 Def
Nature: Sassy
Ability: Synchronize
-Curse
-Wish
-Protect
-Payback
In addition to walling the dark or ghost attacks aimed at Slowbro, this Umbreon basically acts as the physical version of the CalmBro. Though having only one attack is unfortunate, having 100 base power (most of the time) with STAB and no immunities make this acceptable. Umbreon also has very deceptive bulk and can take hits from both sides incredibly well. Wish also gives Umbreon the ability to support the team should it be needed.

Dusknoir @ Leftovers
252 HP / 252 Def
Nature: Sassy
Ability: Pressure
-Trick Room
-Will-O-Wisp
-Pain Split
-Earthquake
Desperately needing something to take the bug attacks that plague many of my other pokemon, I turned to a bulky ghost. I initially used Rotom-H to fire back Overheats, but I've found that this Dusknoir has an incredible synergy with the overall terrible speed that my team has. Trick Room is a move that few people are prepared to counter, especially if they switch into Heatran expecting a Flash Fire boost. Earthquake is chosen as the lone attack for this exact case, since otherwise Dusknoir can do little to beat Heatran despite going first after a Trick Room. Will-O-Wisp helps tame Scizor that can cause a lot of problems, but also works on other physical threats to increase the odds of setting up Calm Minds or Curses. This was initially thought to act as a great support for the rest of my team, but Dusknoir's bulk and impressive attack can help him knock out a few foes on his own as well if the opponent is careless.

Scizor @ Choice Band
252 HP / 252 Atk
Nature: Adamant
Ability: Technician
-Bullet Punch
-U-Turn
-Superpower
-Pursuit
I always liked having a strong U-Turner to scout out opponents, and Scizor is simply the best at the job. His lone weakness is covered by my team's mascot, and the other beefy pokemon on my team can help sponge any other attacks that may be aimed in his direction. This Scizor also has the added bonus of Trick Room, should it be set up, since Scizor's speed is often his downfall.
Conclusion:






Slow and steady wins the race, as they say, and this team attempts to exemplify that. Though Slowbro and Umbreon have the overall bulk to take hits even after they've set up and are running through a team, their speed can often be a liability. Not so with the addition of Trick Room. Dusknoir also has the overall bulk to take a hit, set up Trick Room, then Pain Split damage away to keep itself healthy and running. Breloom is very annoying to anything slower than it, which can be everything depending on whether or not Trick Room is in play or not. The thing that makes this team shine, in my opinion, is that Trick Room simply acts as a bonus to make a set up easier instead of being necessary for success.